The main purpose of the proposal is to develop a system to produce recombinant Nipah virus, which is infectious but not replication competent, and therefore safe to study in a BSL-2/3 fatility Since replication of negative Strand, non-segmented (NNS), RNA viruses is dependent on the presence of the Viral proteins(N, and L)removing those genes from the viral DenoTe abolishes the viruses ability to produce progeny vim& The system developed is totally plasmid based, the truncated genome, N,P And E, and T7 polymerase are a coned into plasmids, and a of the genes except T7 polymerase are under the control of a T7 promoter. These plasmids are transfected into producer cells:0n this case HeLa cells) in attempt to produce virus like particles (VLPs) that contain encapsidated viral genomes. The ratio of N, Piand L: s of the Utmost importance so experiments will need to be conducted to determine what relative ratio of the three produce the greatest amount of VLPs; In addition; to NiP; and L ratios the presence of certain viral proteins sa so thought to affect replication efficiency. Thusly, VLP production will be tested in the presence and absence of these proteins to determine what affect if any they have on Nipah virus replication. The Se studies are particularly important because Nipah is a newly emergent BSL4 pathogen that is associated with a 40% mortality rate, and it is considered to be "weaponizable" and therefore could be used as an agent of bioterrorism.